Further it is observed that certain substantive facts appear in succession; thus, after a ball is struck, we see it move; after a bell is swung, we hear a sound; after we touch fire, a smart follows. The relation by which an antecedent fact is linked to a consequent one we call Succession. Careful attention to the facts of succession is a large part of the work of science, since it is in most cases impossible to bring immediately into existence the phenomena which we desire; we produce them indirectly by producing their antecedents. We do not know why certain simple facts coexist or why certain phenomena resemble each other or why certain things react as they do. These are ultimate facts of the Universe. There is no law of thought necessitating them; consequently they belong wholly to the domain of Induction. That the most refrangible rays of light have a violet color, and that the least refrangible rays have a red color, are facts for which no one expects ever to know a reason. Science makes no progress in this direction. CHAPTER III. OBSERVATION. ९९ THE first step in the discovery of facts is always Observation. In order to know what is passing in our own minds or in the external world, we must give attention. Each act of attention is called an Observation. To quote the words of Bacon : Man, being the servant and interpreter of Nature, can do and understand so much, and so much only, as he has observed in fact or in thought of the course of nature: beyond this he neither knows anything nor can do anything." 1 The five senses report to the mind the world of matter and force; consciousness interprets to the thinking subject his own activities. Perception and consciousness supply the materials out of which the structure of Inductive Science is built up. But thought can build nothing without the use of those primary facts and necessary truths which are known by intuition without the process of discovery. There is nothing peculiar in any process of inference in inductive investigation; for by the nature of the mind there can be but one mode of inference, namely that of deduction. The element of observation is the essential characteristic of Induction. Any syllogism is inductive in which one of the premises formulates the observation of some fact. The great work of Bacon was just this, that he with singular 1 Works, vol. viii, p. 67. clearness, persuasiveness, and charm of language called mankind to patient observation of Nature. A distinction is sometimes made between Observation and Experiment. Dr. Fowler says: "To observe is to watch with attention phenomena as they occur; to experiment (or, to adopt more ordinary language, to perform an experiment) is not only to observe, but also to place the phenomena under peculiar circumstances, as a preliminary to observation. Thus every experiment implies an observation, but it also implies something more. In an experiment, I arrange or create the circumstances under which I wish to make my observation. Thus, if two bodies are falling to the ground, and I attend to the phenomenon, I am said to observe it, but if I place the bodies under the exhausted receiver of an air-pump, or cause them to be dropped under any special circumstances whatever, I may be said not only to make an observation, but also to perform an experiment. Bacon has not inaptly compared experiment with the torture of witnesses. Mr. Mill distinguishes between the two processes, by saying that in observation we find our instance in nature, in experiment we make it, by an artificial arrangement of circumstances." 1 All this is very clear: indeed, it is so clear that one is surprised that the discussion of experiments did not come up in connection with a classification of instances, as natural and artificial. The fact that we can make instances artificially is of great importance in the progress of science; but it is not properly the basis of any distinction regarding the act of observation, which is always the same whatever the origin of the instance. There is no more contrast between an observation and an artificial instance than there is between an observation and a natural instance. Nor is the difference 1 Inductive Logic, p. 40. between natural and artificial instances, that is, between experiments and instances which are not experiments, always clearly traceable. All of the arrangements of human life and society are artificial; we learn from them to our cost, and often, in consequence, change our methods. Popular government is frequently spoken of as still an experiment; the construction of our armored battle ships is experimental. Yet instances of this kind are not arranged for the sake of learning from them, although with the expectation of learning, and improving. The primary rule for any inductive thinking is to make sure of the observations. Starting with prejudices, guesses, or inferences, the truth never can be reached. Nothing but observation can establish a hitherto unknown fact. The explanation of the slow advance of science in ancient and mediæval times may be found mainly in the neglect of this simple rule. In spite of many errors in methods of thinking, the men of those times would have discovered a vast body of facts, if they had only given attention to them. But the making of a precise and trustworthy observation is by no means the easy thing which at first it seems to be. Very much of what passes for observation is merely mistaken inference. An amusing illustration occurs in Charles Darwin's recollections of his father: "He himself never drank a drop of any alcoholic fluid. This remark reminds me of a case showing how a witness under the most favorable circumstances may be utterly mistaken. A gentleman-farmer was strongly urged by my father not to drink, and was encouraged by being told that he himself never touched spirituous liquor. Whereupon the gentleman said, 'Come, come, Doctor, this won't do - though it is very kind of you to say so for my sake - for I know that you take a very large glass of hot gin and water every evening after your dinner.' So my father asked him how he knew this. The man answered, 'My cook was your kitchen-maid for two or three years, and she saw the butler every day prepare and take to you the gin and water.' The explanation was that my father had the odd habit of drinking hot water in a very tall and large glass after his dinner; and the butler used first to put some cold water in the glass, which the girl mistook for gin, and then filled it up with boiling water from the kitchen boiler." 1 To quote from Dr. Fowler : "That which is strictly matter of perception does not admit of being called in question; it is the ultimate basis of all our reasoning, and, if we are to repose any confidence whatever in the exercise of our faculties, must be taken for granted. But there are few of our perceptions, even of those which to the unphilosophical observer appear to be the simplest, which are not inextricably blended with inference. Thus, as is well known to every student of psychology, in what are familiarly called the perceptions of distance and of form, the only perception proper is that of the various tints of color acting on the retina of the eye, and it is by a combination of this with perceptions of touch, and the muscular sense, that the mind gains its power of determining form and distance. Now, a judgment of this kind, which is really due to inference, is, especially by the uneducated and unreflecting, perpetually mistaken for that which is due to direct observation ; and thus what is really only an inference from facts is often emphatically asserted to be itself a matter of fact." 2 To quote from Mr. Mill: "One of the most celebrated examples of a universal error produced by mistaking an inference for the direct evidence of the senses, was the resistance made, on the ground of common sense, 1 Life and Letters, p. 15. 2 Inductive Logic, p. 273. |